This invention relates to an integrated circuit structure having a plurality of inductors arranged so that different pairs of inductors are electrically coupled to one another. More particularly, this invention relates to an integrated circuit structure in which at least three inductors are fabricated adjacent one another in a well in the structure. This invention also relates to power splitters and combiners using such coupled inductors.
It is known that inductors can be formed on the surface of a semiconductor substrate, and that one individual inductor can be coupled to another individual inductor. It is also known that such a coupled pair of inductors can be used as a transformer in, among other things, an RF circuit in which signals must be added or subtracted to perform signal processing and/or modulation/demodulation techniques. However, the coupling coefficient, k, and the quality factor, Q, of such a coupled pair of inductors has been relatively low, and multiple coupled pairs have been required to perform the aforementioned additions and subtractions.
It would be desirable to be able to provide, on semiconductor devices, coupled inductors with high coupling coefficients and quality factors. It would further be desirable to be able to provide a way to efficiently add or subtract RF or other time-varying signals in a semiconductor circuit.